Shareholders' Equity - Progression of the components of accumulated other comprehensive income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	$ (543)
Other comprehensive income (loss), pretax	117	$ (318)
Other comprehensive income (loss), tax	(25)	68
Other comprehensive income (loss)	92	(250)
AOCI ending balance	(451)
Net unrealized gains (losses) on securities:
Unrealized holding gains (losses) on securities arising during the period, pretax	78	(313)
Unrealized holding gains (losses) on securities arising during the period, tax	(17)	66
Unrealized holding gains (losses) on securities arising during the period, after tax	(61)	247
Reclassification adjustment for realized (gains) losses included in net earnings, pretax	29	2
Reclassification adjustment for realized (gains) losses included in net earnings, tax	(6)	0
Reclassification adjustment for realized (gains) losses included in net earnings, after tax	23	2
Total net unrealized gains (losses) on securities, pretax	107	(311)
Total net unrealized gains (losses) on securities, tax	(23)	66
Total net unrealized gains (losses) on securities	84	(245)
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Unrealized holding gains (losses) on cash flow hedges arising during the period, pretax	5	(4)
Unrealized holding gains (losses) on cash flow hedges arising during the period, tax	(1)	1
Unrealized holding gains (losses) on cash flow hedges arising during the period, after tax	4	(3)
Reclassification adjustment for investment income included in net earnings, pretax	5	(1)
Reclassification adjustment for investment income included in net earnings, tax	(1)	0
Reclassification adjustment for investment income included in net earnings from discontinued operations, after tax	4	(1)
Total net unrealized gains (losses) on cash flow hedges, pretax	10	(5)
Total net unrealized gains (losses) on cash flow hedges, tax	(2)	1
Total net unrealized gains (losses) on cash flow hedges	8	(4)
Foreign currency translation adjustments, pretax	0	(2)
Foreign currency translation adjustments, tax	0	1
Foreign currency translation adjustments	0	(1)
Total pension and OPRP adjustments, pretax	0	0
Total pension and OPRP adjustments, tax	0	0
Pension and OPRP adjustments	0	0
Accumulated net investment gain (loss) attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(497)	136
AOCI ending balance	(413)	(109)
Accumulated gain (loss), net, cash flow hedge, parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(29)	0
AOCI ending balance	(21)	(4)
Accumulated foreign currency adjustment attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(20)	(18)
AOCI ending balance	(20)	(19)
Accumulated defined benefit plans adjustment attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	3	1
AOCI ending balance	3	1
AOCI attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(543)	119
AOCI ending balance	$ (451)	$ (131)